Compressor



Sept. 28, 1937. M. KENNEY ET AL v I 9 COMPRESSOR Fil'ed Aug. 26, 19:55, 3 She ets-Sheet 1 JGL Sept. 28, 1937. M. w. KENNEY ET AL couPnEssoR Filed Aug. 26, 1935 3 Sheets-Sheet 2 huenibrlsi 1 161, 6. Cfiq: wz w P 937- Y M. w. KENNEY -r AL 2,094,323

COMPRESSOR v Fiied Aug. 26, 1935 3 Sheets-Sheet 3 Patented Sept. 28, 1937' UNITED" STATES PATENT OFFICE 2,094,323 COMPRESSOR Mahlon W. Kenney and Arthur R. Constantine, River Forest, 111., assignors, by mesne assign-- ments, to Reconstruction Finance Corporation,

Chicago, 111., a corporation Application'rAug'ust 2c, 1935, Serial No. 37,861 3' Claims. (01. 230-452) Our invention relates in general to fiuid-dynamics and more particularly to fluid-flow demany features of the invention may have genera. application in fluid dynamics. The device of our' present invention, however is particularly well adapted for use as a compressor in a refrigerating system wherein a suitable refrigerating medium, in gaseous condition, is: compressed,

then liquefied and finally evaporated for the absorption of heat, the gases, evolved by the evaporation of the refrigerating medium, being returned to the compressor for a repetition of the refrigerating cycle.

Another important object is to provide a mechanism of the character mentioned, which is com pact, efficient, and substantially noiseless in operation and whichis sealed against the escape of the working medium, the mechanism including driving means for the compressor, which, with. the compressor mechanism, is enclosed in a sheet metal housing whereby to reduce the cost of construction and, at the same time, promote heat dissipation to maintain the unit at a low efficient operating temperature.

Another important object is to provide a motor-compressor unit having a hermetic enclosure entirely of sheet metal.

Another important object is to mount the dynamic mechanism in a sheet metal shell by suspending the same directly on the shell'whereby the resilience of ,'the sheet metal itself serves to resiliently support the operating mechanism. 40 Another important objectis to provide threepoint suspension of an operating mechanism within a sheet metal shell in order to improve its mounted'stability, Another important object is to support a com.- pressor or pump and its driving motor on opposite ends of a shaft journalled intermediate its ends in a single bearing formed in a support frame, which, in turn, is carried entirely on a sheet metal shell;- j

Another important objectis to provide a device having a rotating element carrying blades projecting from the working surface of the element so that the outer edges of the blade may perform a dynamic function with a fluid work medium, while the portions of the blade, cartaken in connection ried by. and within the rotary element, are utilized to pump a lubricating medium to desired places of the compressor and motor requiring lubrication. I

Another object is to utilize the moving ,ele-= 5 merit of a dynamic device to accomplish a plurality of dynamic functions with corresponding work media.

Another important object is to provide a pump or compressor comprising a cylinder immersed 10 in a lubricating medium and including a rotary piston within the cylinder having fluid-forcing blades reciprocating on the piston during rotation thereof within the cylinder in order to perform a dynamic function upon a fluid medium 15 in the cylinder, said cylinder having a lubricant port disposed with respect to the piston so that the reciprocating action of the blades in the pistonmay be utilized to draw lubricant through said port and into the interior of the piston and 2 expel the same thence to any desired place re quiring lubrication; 'a further object being to discharge the lubricant, so pumped, to the piston bearing in order to lubricate the same.

Another important object is to provide a lubri- 25 cant duct surrounding thebearing and to deliver an excess of oil through said duct for the purpose of cooling the bearing.

Numerous other objects, advantages, and inherent functions of the invention will be ap- 30 parent from the following description, which,

with the accompanying. drawings, discloses preferred embodiments of the invention.

Referring to the drawings:

Figure 1 is a vertical section through a sealed unit, embodying our present invention and comprising a motor, a compressor and support means therefor including a frame carrying a,

lubricant-cooled main bearing and an enclosing 40 housing of sheet metal; Figure 2 is a horizontal section taken substantially along the line 2-2 in Figure 1;

Figure 3 is a horizontal section taken substantially along the line 3-3 in Figure 1; 45

Figure 4 is a perspective view of a bushing forming a part of the lubricant-cooled bearing;

Figure 5 is a perspective view of parts forming the cylinder of the compressor element;

, Figure 6 is a perspective view of parts forming 50 the compressor piston;

Figures 'l and 8 are perspectiveyiews of the co-operating parts of the sheet metal housing;

Figure 9 is a perspective view of the support frame; and

leg for the housing.

To illustrate our invention, we have shown on the drawings, a fluid-forcing device particularly adapted for use as a compressor in a refrigerating system ofthe compression-evaporation type, although it will be obvious that the invention is not necessarily restricted in all of its features to compressors or to devices used in refrigerating systems. On the contrary, the invention includes many features which may be incorporated to advantage in fluid-dynamic devices generally.

We propose the features of our present invention, however, more particularly for application in fluid-forcing means adapted for substantially noiseless, leak-proof, and eflicient operation overlong periods of time without attention in order to produce a preferably motordriven compressor for use in refrigerating systems wherein the foregoing characteristics are desirable.

Compressors, made in accordance with our present invention, are particularly well suited'for use in domestic refrigerators where simplicity and cheapness of construction, and silent, as well as trouble-free, operation over long periods of time without attention are highly desirable features.

The illustrated motor-compressor mechanism comprises a sealed unit including fluid-dynamic means l3, namely a compressor, and dynamo-electric means |5, namelyan electric motor, preferably of the induction type, drivingly connected with the compressor, said compressor and motor being sealingly enclosed in a preferably hermetic housing I! of sheet metal. The housing preferably comprises a pair of sheet metal shells I9 and 2| for the sake of convenient as-' sembly. The fluid-dynamic and dynamo-electric devices l3 and 5 are supported in and by said sheet metal housing so that the entire weight of said devices is carried by the relatively flimsy and resilient sheet metal walls of the housing.

The motor |5 preferably comprises a stationary portion or stator23, carrying windings 25, and a movable portion or rotor 21, and the compressor |3 comprises a cylinder 29 and a piston 3| within the cylinder and forming therewith a compression or working space 33. The cylinder 29 and piston 3| are relatively movable to perform a fluid dynamic function with a fluid work medium within the working space 33. We prefer to form the cylinder as a stationary element while the piston is rotatable within the cylinder and about an axis 61 eccentric with respect to the axis 69 of the cylinder. I

All of the parts of the mtor and compressor are supported preferably upon a frame or spider 35 comprising an annular rim 31, a central hub 39 and arms 4| interconnecting the hub and rim. The rim 31 is formed with a seat 43 adapted to receive the stationary element 23 of the motor, which is secured in place by preferably elongated fastening elements 45 extending through the stator 23 and threading into openings 41 in the rim 3'! opposite the legs 4|.

The compressor cylinder 29 comprisesa cylindrical element 49, the innerbore of which deflnes the outer surface of the compression space 33. One end of the element 49 is secured to an end of the central hub 39 by means of headed studs 5| passing through a flanged portion 53 of said hub and threading in sockets formed in the end of the element 49. The walls of the element 49 Figure 10 is a perspective view of a supporting.

which are received headed fastening members 51, which takeinto the hub portion 53 and additionally secure the cylinder element 49 on the hub.

The other end of the cylinder element is closed by a cover 59, comprising a preferably circular disk secured on the end of the element 49 by headed fastening members 6|, which penetrate perforations formed in the disk 59 and thread into openings 63 formed in the end of the cylinder eleframe 35.- The cylinder fastening elements 5| and 51, however, afford means for adjusting the position of the cylinder slightly on the hub 39 during assembly so that the parts may be arranged to providerunning contact between the outer surface of the piston and the inner bore of the cylinder along a line 68 lying in a plane common to the axes 61 and 69 so that the work space 33, defined between the piston and cylinder, is crescent shape in cross-sectional configuration with the horns of the crescent extending unopposite sides of the line of contact 68. I

The outer surface of the cylinder element is flattened to form a seat substantially opposite the line of contact 68 and a preferably sheet metal housing 13, comprising a cup-shaped element, is secured with its edges in engagement on the seat II. This cup-shaped element is held in place by means of a headed fastening stud 15 extending through its wall and threading into a suitable opening 11 formed in the walls of the cylinder element 49.. The housing 13 forms a receiving chamber 19 and the cylinder is formed with a plurality of openings 8| comprising discharge ports communicating-an arm or horn of the work space, on one side of the contact line 68, with the interior of the receiving chamber I9.

The cylinder element also is formed with a slot opening upon the other arm of the work 4 space on the side of the contact line .68 opposite from the ports 8|. The walls of the cylin-v der element are formed with a channel or duct extending from the slot 83 to the end of the element, which is secured to the end of the hub. One of the legs 4| of the frame is enlarged, as at 81, said enlargement containing a duct 89 opening at one end on the surface of the hub 39 in communication with the channel 85. The duct 89, at its other end, opens outwardly of the cylinder element.

As heretofore mentioned, the hermetic casing l1 preferably comprises a pair of co-operating shell-like portions l9 and 2|, which may be conveniently formed of sheet metal in any suitable fashion, as by pressing or otherwise forming metal sheets of gauge suitable for desired strength in the flnished casing. The casing portions are preferably of cup-shaped configuration having marginal flanges 93, by meansof which the same may be secured together in any suitable fashion, said flanges-being provided with a series of circularly arranged registering perforations 9| and secured together, upon an intermediate. sealing gasket 95, by and between a pair of annular rings 91 and 99. The ring 91 underlies one of the flanges and is formed with threaded openings II in position aligning with the flange perforations 9|. The ring 99 openings I 03 adapted to align with the openings 9i; and the parts are clamped together preferably by headed studs I95 penetrating the openings I03 and 9E and threading into the openings Illi. f i

We also preferably provide means comprising a plurality of legs for supporting the casing and the mechanism enclosed therein. These legs preferably comprise each an elongated element Hi1 having a threaded socket I09 at one end whereby the same may be attached to the threaded end Ill of one of the studs E05, certain of which extend beyond the ring 91 in position to carry the legs. of -this character may be used. Any suitable means may be utilized to mount or secure the legs Hill on a supporting base but we prefer to utilize a resilient mounting construction wherein the lowerend of. each leg till provides a shoulder H3 seating on a washer H5, which, in turn, is supported in a resilient, preferably rubber, mounting block M1. The mounting block H1 is preferably enclosed in a shell-like element M9, by means of which it is secured on the base IZI. The leg 801' has an extension penetrating the washer H5 and a weblike portion I23 of the resilient mounting block and carrying, on its threaded end, a washer and a suitable holding nut for the purpose of securing the leg on the resilient. mounting block.

To support the motor and compressor on the.

shell, the frame 35 is provided'with a pair of cars I25 formed on the enlarged portion 53 of the hub 39. These ears I25 project outwardly in position to rest upon and be supported by 'fianged hangers I21 formed or otherwise secured on the shell element 2i. The ears I25 and hangers I21 are preferably perforated to permit the parts to be bolted together. In addition, a fitting I29 is mounted on the wall of the shell element 2|, at an opening I 3| formed therein. The fitting I29 has a nipple I33 extending through the opening and sealingly secured therein so that the fitting I29 forms a hanger on which to support the enlargement 81 of the frame, said parts being preferably secured together by fastening elements passing through openings I38 in the fitting I29 and corresponding openings I31 in the frame portion '31. v

The fitting I29 is formed with an enlarged chamber I39 opening into the duct 89 of the frame'when the same is positioned on the fitting I29. The lower portions of the chamber I49, which is held in place, when the frame is connected on the fitting I29, by 'means of a pin I5I carried by the frame and having an-end projecting in position to engage the guard and prevent shifting of the same within the chamber. The nipple I33 is formed with a duct I53 communicating with the valve chamber I39 and opening outwardly of the casing through the end of the nipple, which is threaded, as shown, to facilitate attachment of a conduit I55, through which a work medium may be delivered through the duct I53 and the valve chamber and into the duct 89 of the frame, thence through the duct 85 to the inlet space 83 of the compressor. Rotation of the piston relative to the cylinder in a. direction as shown by the arrow in Figure 2 Three or more legs resilient of the drawings will cause the work medium to be compressed in the work space 33 and dework medium may be delivered from the compressor and which is adaptedto muffle or suppress the noise of expulsion of the work medium under pressure'frorn the compressor. During the operation of the device, the work medium consequently is delivered into the housing ll, which, of course, becomes loaded'with the work me dium at the delivery pressure of the compressor. The compressed medium may be delivered from the casing through a nipple or nozzle 159 preferably sealed in an opening formed in the casing portion I9, the external portions of said. nozzle being threaded for connection with suitable conduit means, through which delivery of the compressed medium may be made to any desired place of use.

The shaft 65 has an end extending upwardlyv of the hub portion 39 of the frame and formed to receive and support the rotor 21 of the motor,- said upwardly extending end being preferably tapered, as at I6I to receive a correspondingly tapered -sleeveI63,-which,may beheld on the shaft by means of a washer I65 and a threaded stud I51, which engages in a threaded socket formed in the end of the shaft. The sleeve I63 carries a depending frame I69, on which the rotor 21 is con-,- structed.

The shaft 65 preferably is formed with a pair of spaced apart bearing portions HI and isreceived in a sleeve-like bushing I13 having a preferably spiral groove I15 cut in its inner surface for purposes of aiding lubrication of the shaft bearings. The outer surface of the sleeve I13 is preferably formed with a plurality of parallel grooves I11 disposed on one side of and at one end of the sleeve, the end-of thesleevebeing notched as at I19 to connect one of said grooves I 11 with an end of the spiral groove I15. The sleeve I13 is firmly fitted into the hub 39 of the frame, which is provided interiorly with an annular groove I 8I The groove I81 communicates with the outer surface of the hub 39 through a duct I83. The annular groove I8I is positioned in the hub to communicate with the grooves I11 of the bearing sleeve.

The piston of the compressor is provided with a plurality of channels I85, extending parallel with and spaced from the piston axis 61 andslots I81 are formed in the body of the piston radially of said channels. These slots, as well as the channels I85, extend from end to end of the piston element and a fluid-forcing blade or vane I89 is arrangedin each slot. These blades are long enough to slidingly engage the facing sur faces of the cover 59 and the hub 39 of the frame at their opposite ends and are slidable in the slots I81 so that the outer edges of the blades, which are slightly rounded, may bear upon the inner surface of the cylinder at all times during the rotation of the piston therein.

The driving motor, whenenergized. is adapted to rotate the piston within the work chamber in'a direction causing the blades to sweep across the connected with the inlet space 83 to the arm which is in communication with the outlet ducts 8I whereby to force. fluid, delivered at the inlet, through the chamber and thence under pressure into the muiller chamber 19. The blades 489, however, are freely depressible in the slots and consequently, during operation of the compressor, will reciprocate therein and establish an auxiliary pumping action in the channels I85, the blades, of course, being urged outwardly in the slots by centrifugal action and being depressed as the outer edges of the same rideupon'the cylinder toward the contact line 68. i

We utilize this auxiliary pumping action in order to supply a suitable lubricating medium to the operating parts requiring lubrication and particularly to the shaft bearing. To this end, the casing part 2i provides a reservoir of a suitable fluid lubricating medium I9I, which normally fills the same to an approximate level indicated in Figure l by the line I93. The lower end of the compressor is'thus immersed in the lubricating I channel I85 is out of communication with the inlet opening I 91. Consequently oil will be drawn successively into the channels I85 through the oil inlet I95 and will be compressed in the channels I85. The ends of the channel I85, facing the hub 39, are successively brought into communication with the grooves I11 during the rotation of the piston when the blades move inwardly in the slots, so that the lubricant, compressed in said channels I85, may be delivered to said grooves from whence an excess of lubricant may penetrate into the annular groove I8I and escape through the duct I83, thus serving to cool the bearing and the hub 39, and thence flow by gravity back to the lubricant reservoir I9I.

A part of the lubricant, however, will be forced into the lower end of the groove I19 and thence through the shaft bearing to lubricate the same,

the lubricant escaping at the upper end of said bearing and returning by gravity to the reservoir. A part of the lubricant may alsoescape from the channels I85 through the slots I91 on'- opposite sides of the blades in order to provide the reciprocating blades with adequate lubrication; Such oil, of course, enters the work space and will be expelled together with the work medium into the chamber 19 and will be forced through the tube I51 and out into the housing I1, whence it may return to the reservoir I9I.

If the compressor stands idle for any length. of time, lubricant from the pool or reservoir |9l may escape into the compressor andflood the same and the chamber 19 to the level of the oil in the reservoir I9I. For thisreason, it is desirable to provide for the rapid ejection of excess lubricant when the compressor is started in operation,

and, at the same time, permit delivery into the casing of such gases as may be in the chamber 19.

To this end, the upper portion of the shell 13 is formed with an opening I99, in which is seated a check valve 20I comprising a ball which is held in crescent shaped work space from the thereof place by suitable retaining means 203. Of course, any suitable form of check valve may be used. As soon as the compressor starts in operation, oil will be forced rapidly through the-pipe I51, due to the development of excess pressure in the chamber 19. The excess pressure, developed in the chamber 19, will also raise the ball 20I from its seat and permit any gases, that are delivered in the chamber 19, to escape directly into the housing I1 together with any excess oil. The pipe I51 extends substantially to the bottom of the chamber so that the chamber may be substantially cleared of oil rapidly while the check valve permits compressed gases to enter the housing while the chamber 19 is being purged of oil. Theoil ejected from the chamber 19 returns immediately to the reservoir I9I. After the oil has thus been exhausted from the chamber 19, the pipe I51 may carry substantially all of the compressed gases and deliver the same into the housing I1, the check valve, under such conditions, remaining closed.

Any suitable means may, of course, be utilized for powering the motor I from a suitable power source located externally of the casing. We pre fer, however, to provide sleeve-like bushings 205 threaded or otherwise sealingly secured in open ings 201 formed in the casing element I9. These bushings each carry a conductor 209 embedded in suitable insulation 2| l, the opposed ends of each conductor 209 being held in insulating washers 2 I 3 at opposite ends of its corresponding bushing 205. The ends of the conductors 209, exposed within the casing, may be connected in any convenient manner with the motor windings 25, while the outer ends of the conductors may be connected by suitable cable means 2 I 5 with the power source from which the motor is to be energized. The connectionbetween the cable means 2I5 and the outer ends of the conductors 209 may be covered by suitable, preferably rubber, insulating caps-2I1. v I i As heretofore mentioned, motor-compressor units, embodying our present invention, are esperefrigerant, when in (gaseous condition, is substantially insoluble in mineral oils so that substantially'no problem of separating the gaseous refrigerant from the, liquid lubricant is encountered. The lubricant simply settles to the bottom of the casing I1, while the compressed refrigerant escapes through the nozzle I59 at the top of the casing.

It is thought that the invention and numerous ofits attendant advantages will be understood from the foregoing description and it is obvious that numerous changes may be made in the form, construction, and arrangement of the several parts of the illustrated apparatus without departing from the spirit orscope of our invention or sacrificing any of its attendant advantages, the preferred modes and forms herein described being merely for the purpose of illustrating the invention.

Having thus described our invention, what we claim as new and desire to secure by Letters Pat-- entis as follows: I

terior of said cylinder, at least one of said elements having a shaft extending within and journalled in said sleeve, means on said frame for driving said shaft and the element connected thereto, means formed and arranged on said driven element for delivering fluid under pressure to said longitudinal grooves, said bearing support having duct means communicating with said grooves and extending in and through said bearing support for the purpose of receiving cooling fluid.

2. A device of the class described comprising a frame, fluid dynamic means carried by said frame and comprising cooperating working elements including a piston element and a cylinder element forming a working space on one side of said frame,

said frame forming a bearing support, a sleeve fitted in said bearing support having longitudinal grooves in the outer surfaces of the sleeve at an end thereof communicating with the interior of said cylinder, at least one of said elements having a shaft extending within and journaled in said sleeve, means on said frame for driving said shaft and the element connected thereto, means f o'rmed and arranged on said driven element for'delivering fluid under pressure to said longitudinal grooves, said bearing support having duct means communicating with said grooves and extending in and through said bearing support for the purpose of receiving cooling fluid, an opening in said sleeve communicating at least one of the longitudinal grooves with the interior'of the sleeve whereby a lubricant delivered in said groove may enter the sleeve to lubricate the shaft extending therein.

3. A device of the class described, comprising a. pair of cooperating shell sections of generally cup-shaped configuration having outwardly extending integral marginal flanges at the edges thereof whereby said shells may be secured together to form a hermetic casing, said flanges also affording means for the attachment of support members for mounting the casing in operative position, working mechanism within said casing comprising a frame forming a plate portion, an annular ring-like rim and arms interconnecting the rim with said plate portion, said plate portion having a shaft bearing, fluid dynamic means forming a working space and mounted on one side of said plate portion in position extending within one of said cooperating shells, said shell having bracket means on the inner walls thereof in at least three circumferentially spaced locations, said frame having at least three mounting portions adapted to rest upon and be secured to said bracket means whereby to support the mechanism within the hermetic casing, said fluid dynamic means comprising a cylinder on said plate portion and a piston within the cylinder, a shaft extending through and journalled in said bearing and drivingly connected with said piston, a driving motor extending within the other shell portion and having an annular stator mounted on said rim and a rotor within said stator and drivingly connected on said shaft, at least one ofsaid bracket means forming a channel opening outwardly of said hermetic casing and said fluid dynamic means having an inlet duct including a duct portion extending in said frame and communicating with the channel of said bracket means, said other casing portion having an outlet fitting thereon and at least one of said casing portions having gas-tight conductor inlets to permit said motor to be electrically energized from a source outside of said casing.

MAHLON W. KENNEY. ARTHUR COITSTAN'I'INE. 

